Detecting and managing information on various commodities by using semiconductor elements mounted on the commodities has been widely performed. Such semiconductor element is mounted, as a tag mounted on a substrate having a coil conductor, on various commodities. Transmission and reception of information is performed between the semiconductor element and an external device such as a reader/writer having a radio wave transmitting/receiving function.
The transmission and reception of information between the semiconductor element and the external device is performed by using the radio (RF) communication. An induced current is generated in the coil conductor by a magnetic flux caused by the radio wave transmitted from the external device, and an electric power necessary for the operation of the semiconductor element including writing and reading the information is supplied (refer to PTL 1, for example).